The thought of “synchronized swimming” may call to mind the Olympic event or perhaps white-capped women in old Hollywood musicals. But there’s another mammal that uses synchronized swimming — and it’s not just to show off.

Long-finned pilot whales synchronize their swimming when they sense danger. Researchers made this discovery when comparing two populations of pilot whales, one in the Strait of Gibraltar off the Spanish coast and one near Cape Breton on Canada’s east coast.

Deep below the Arctic Ocean lies a mid-ocean ridge system that meanders for 1,100 miles along the sea floor. Mid-ocean ridges, essentially underwater mountain ranges, form when magma rises up from deep within the Earth to fill the gap between two tectonic plates that are moving away from each other. At the northernmost section of this ridge system is the Gakkel Ridge, rising up between the North American Plate and the Eurasian Plate.

Perhaps it’s not surprising that a creature as fierce looking as the angler fish has pretty extreme mating habits — starting with a never-ending love bite and ending in death. Angler fish have long, sharp, ferocious looking teeth, but only the females use these for eating. The males use theirs on the females.

The vampire squid sounds like a hostile creature from the Twilight Zone, but it’s really the environment these harmless cephalopods live in that’s hostile — the dark, cold “midnight zone.” The vampire squid lives in the middle of the ocean’s five vertical ecological zones, an area about a half mile to two and a half miles deep called the bathypelagic zone.

You might think a creature called the vampire squid would suck the blood of an unfortunate passing fish. After all, other octopus and squid species hunt live prey. Instead of preying on the undead, however, the vampire squid simply feasts on the dead.

It’s no secret that most animals release waste through their backsides, but some use that exit for more than releasing leftover food. Sea cucumbers use their rear end for at least five different functions — including breathing.

Sharks may be top predators in the sea, but they can be prey as well, especially as babies. Researchers have learned that young sharks can sense nearby predators and then act to avoid detection — even when still in their egg case.

Biologists already knew sharks can sense possible prey by detecting electrical fields produced by nearby fish. However, scientists did not know whether shark embryos would adjust their own biological processes to reduce their risk of being discovered as prey themselves.

If the home that gives you shelter and houses your food were threatened, you’d likely do what you could to protect it. Gobies are no different. These tiny fish — just an inch long —live in coral, which protects them from predators and lets them eat algae on the coral and plankton from the surrounding water. But the coral sometimes needs protection too, and gobies are up to the job.

You’ve heard of whales singing, but what about talking? If that sounds crazy, most marine biologists would have agreed until they had heard it — a whale trying to imitate human speech. In fact, they had not realized it was physically possible for whales to make those kinds of sounds until a beluga whale named NOC spoke up.